(a) Field of the Invention
The present invention is related to a chip packaging overflow proof device, and more particularly to a package base including an overflow space to contain squeeze-out.
(b) Description of the Prior Art
The conventional manufacturing process for semiconductor package with lead frame as a chip carrier, e.g., Quad Flat Package (QFP) or Quad Flat Non-Leaded (QFN) involves having the lead frame provided with a chip base and multiple guide pins to be adhered with a semiconductor chip; the lead frame is then electrically connected to a solder pad and multiple corresponding connection pins with multiple golden plated wires, and finally a packaging colloid is provided to encapsulate the chip and those golden plated wires to form a semiconductor package. Meanwhile, on surface of the chip base may be exposed out of the packaging colloid for the chip base to facilitate dissipating the heat built up on the chip.
Referring to FIGS. 1 and 2 of the accompanying drawings for a process of packaging multiple chips, each chip 11 is disposed on a same substrate 12 and the substrate 12 is related to a circuit board with both sides disposed with circuits 13. The substrate 12 and multiple chips 11 are placed in a packaging base 14. Both sides of the packaging base 14 are respectively provided with a socket 15 to receive insertion by a lid 16. A cable-terminating hole 17 is disposed at where between the socket 15 and the lid 16 for the circuit to penetrate through. A packaging colloid 18 is filled above the substrate to protect those chips 11 while each chip 11 is activated when the circuit 13 is conducted.
The cable-terminating hole 17 is contained in a first slot 171 with its opening facing upward and disposed at the bottom of each of both sides of the socket 15 and in a second slot 172 with its opening facing downward and disposed on the bottom of each of both sides of the lid 16. Once each lid 16 is inserted into the socket 15, both of the first and the second slots define the substantially circular cable-terminating hole 17 to allow the circuit to penetrate through. Upon filling the packaging colloid 18, squeeze-out occurs on the external side of the packaging base 14 when the colloid 18 is vulnerable to flow out of the cable-terminating hole 17 due to excessively filling amount of colloid 18 or excessively higher viscosity of the colloid 18 as illustrate din FIG. 2. In case of squeeze-out, not only the appearance is compromised and extra process cost is incurred from ridding of the squeeze-out, but also the binding strength between the colloid and the packaging base may be affected.